The menopause transition is associated with a pronounced increase in risk of cardiovascular disease. We will examine the impact of hormone replacement therapy on metabolic risk factors affecting cardiovascular disease in early postmenopausal women. A total of 88 women will be recruited for this 2-year randomized double-blinded placebo-controlled longitudinal study. We will measure outcomes of changes in body fat distribution and insulin sensitivity on 4 occasions (baseline, 6 months, 1 year, and 2 years) in women taking continuous conjugated estrogens plus medroxyprogesterone acetate or placebo. Our study will assess the temporal sequence of changes in outcome variables to provide insight into whether changes in body fat distribution precede alterations in insulin sensitivity, and whether hormore replacement therapy prevents these changes.